Paper bag



March 9, 1937. F. G. ROBINSON PAPER BAG Filed' Aug. 24, 1935 5 sheets-sheet 1 Z VAE March 9, 1937- F. G. ROBINSON 2,073,222

PAPER BAG Filed Aug. 24, 1955 5 Sheets-SheecI 5 fly/f March 9, 1937. F, G ROBINSON 2,073,222

PAPER BAG Filed Aug. 24, 1955 5 Sheets-Sheet 4 /n ven/Tfr* March 9, 1937. F. G. ROBINSON 2,073,222

PAPER BAG Filed Aug. 24, 1935 5 Sheets-Sheet 5 Patented Mar. 9, 1937 UNITED STATES lPATialvT ori-ics Application August 24, 1935, Serial No. 37,757 In Great Britain September 11, 1934 25 Claims.

This invention relates to paper or like bags or sacks in which the marginal portions of the ends of the bag tube are folded to form what is usually called a blockbottom, and is especially intended for application to heavy duty multiply bags or sacks although the invention may be applied to bags or sacks having only a single ply or wall.

If the mode of folding of the known blockbottomed bags be examined, it will be seen that in folding the end of the bag tube to produce the blockbottom, end portions or flaps (those parts adjacent the end of the side edges of the flattened tube) have been folded inwardly and that side portions or flaps (the extremities of the faces of the flattened tube) have been folded over the end flaps and one upon the other, so that the side flapsoverlap one another and also overlap the end flaps.

It will be further noted that in folding in the end flaps and subsequently folding over the side flaps, a reentrant angle is constituted so that the seam across the elongated blockbottom is shorter than the width of the bag. In blockbottoms of this character it is necessary to form a seal be- 25 tween the side flaps and the end flaps and this is usually done by the use of adhesive. Or, in the vcase of multiply bags adhesive is used between the plies and the seam is stapled. Moreover, in some cases it is necessary to apply a 30 separate outer strip or piece to eiect a seal. In order to provide a sufficient covering closure the mutual overlap of the sides and end flaps must be extensive, or, in other words, the aps must be unduly large, which has the eiect of decreas- 35 ing the capacity of the bag for a given length of tube, and a notching of the corners of the flat tube which has been resorted to does not remove the objection and is not entirely satisfactory. These known methods are liable to produce a 40 bottom closure .which is unduly rigid and lacks the flexibility desirable in heavy duty sacks.

An object of the present invention is to provide an improved bag and mode of forming a bag to produce a blockbottomed bag closure which is D more durable, flexible or stronger and in which in particular the corner construction is flexible and more robust.

An advantage of the invention is also that for a given length of tube a bag of slightly greater capacity can be made than by the previously known method of forming a bag closure on the blockbottom principle.

Another object of the invention is to produce an improved multiwalled blockbottomed bag, or an improved multiwalled valved bag of improved blockbottom construction at both ends, an advantage of the invention being that the bottom and ends of the bag may be securely closed by the use of adhesive. y

The invention consists in folding the end aps of a bag tube inwardly and then outwardly before the side flaps are closed over upon one another. In the improved bag an additional flexible corner piece of triangular shape is provided which forms an extension of the normal bag 5 space. Viewing the blockbottom end of the improved bag, the triangular extension piece, when flattened upon the bottom, coincides with the angular end of the blockbottom formation lying at the side edges of the flattened tube. The walls of the corners of the bag will be continuous with the walls of the bag and of the same thickness, thereby producing a corner of considerable strength secured by the sealing closure of the bag which lies equally on each side of the longitudinal centre line of the bottom affording increased thicknesses while preserving flexibility.

The invention further consists in the provision of blanks or sheets for the formation of multiply bags, having their end edges notched as hereinafter described so as to provide overlapping margins or headings on one side of thevtube securable to corresponding margins on the other side of the tube, either by superixnposition or by interleaving, in either case forming in effect a series of independent nested bags. This method of construction can be carried out with the minimum of waste by cutting the blanks from a series of webs of appropriate width, each cut or severance producing the head of one blank and the tail of the next, so that the heads and tails are counterparts one of the other.

According to one form for making a multiwalled bag or sack having an interleaved closure, the corners of flattened nested bag length tubes are cut off at 45, a distance sufficient to give the necessary overlap or interengaging margins for sealing wlith an adhesive. Alternatively, the blanks from which the tubes are formed are cut with 90 notches at the extremity of the tube folding lines. The end of the tube is opened and the end flaps are folded inward and then they are raised and at the same time turned or folded back upon themselves. The side flaps are then turned upwardly and are folded towards one another so as to bring them in overlapping relation. In uniting the edges the margins of the plies are interleaved from one notched portion to another and secured to one another by adhesive.

According to another mode of forming what may be called a stepped tube, or a. nested bag tube in which the ends of the tubes are staggered or have projecting headings so as directly to overlap when folded over one upon the other, sheets are cut or blanks are severed from webs of appropriate width so as to produce a series of blanks having wide notches and shoulders. Severance is effected in three places. Cuts Nos. 1 and 2 are in the same straight line on the outer 30 parts of the web while the inner cut No. 3 lies parallel with and spaced from cuts Nos. 1 and 2. These cuts are connected by short cuts running diagonally or obliquely from the inner ends of cuts Nos. 1 and 2 to the adjacent ends of cuts No. 3 thus forming a wide notch with shoulders on each side and leaving on tl-e web a counterpart formation. The distances between the transverse cuts considered longitudinally of the web will vary on each web forming a set for a composite nestedtube, the arrangement being such that the diagonals or oblique edges formed by the short'cuts on each ply will coincide or cross oneanother at points which will lie on the l5 longitudinal side folds of the tubes.

The sheets, notched after the manner described, are assembled (preferably in laterally staggered relation) and formed into tubes, the end flaps are folded inwardly and outwardly and the side flaps are folded over so that the protruding margins or headings provided on one side or face of the tube lie in overlapping register with the corresponding margins or headings on the other side or face of the tube, to which they are united by adhesive.

A valve (or valves) is formed by providing short longitudinal cuts in the ends of the notched tubes parallel to the sides or longitudinal folding lines of the tube in order to provide a sufficient length of ilap or tongue to enable the valve securely to close or lock after lling.

In the accompanying drawings:-

Figure 1 is a diagram showing how a series of independent webs are cut for making sets of blanks for tube forming, the cuts being arranged so that allowing for the margins or headings the heads and tails of each sheet cut from any one web are the same. In this gure the webs are shown superposed for the convenience of space.

Figure 2 shows the end fragments of sheets cut from webs as in Figure 1 assembled in superposed laterally staggered form to provide a series of blanks for forming a tube for a four-ply bag according to one form of the invention, the length of the sheets being according to the length of bag to be manufactured.

Figure 3 shows one end of a nested series of tubes formed from the sheets shown in Figure 2 before the blockbottom forming operations are commenced.

Figure 4 is a sectional view showing the projection or heading margins of the tube ends on each side or face of the tube to provide for overlappable` margins.

Figure 5 is a face view of the end portion of the nested tubes seen in Figure 4 illustrating the first stage of folding the side and end flaps of the composite tube.

Figure 6 is an enlarged view showing the end flaps being folded outward upon themselves.

Figure 7 is a view illustrating a slightly later stage of folding to that in Figure 6 and showing one side flap to have been folded inwardly and the other side iiap about to be folded down thereon and secured.

Figure 8 is a fragmentary plan or end View of the bottom closure of the bag after the overlapping margins have been secured by adhesive one upon the other andthe blockbottom formation Figure 13 is a. view illustrating the application .of an extra piece applied to the valve end flap in order to cover the V-shaped notch seen in Figure 12.

Figure 14 shows the completed valve closure. Figure 15 is an illustration corresponding with Figure 5 but illustrating the application of the invention to a bag tube having gusset folds.

Figure 16-is a perspective view illustrating a completed gusseted bag with a blockbottom formation according to the invention and showing the extra triangular projecting pocket.

Figures 17 to 21 are fragmentary views illustrating a modification of the invention in which the plies are interleaved at the closure.

Figure 17 shows a series of blanks superimposed and notched on the longitudinal folding lines of the tubes.

Figure 18 shows the blanks illustrated in Figure 17 folded into tube formation and also illustrates how the notches seen in Figure 17 can be produced by cutting off the corners at 45 when the tubes have been formed.

Figure 19 is a view showing the inward folding of the end flaps corresponding to Figure 6 above.

Figure 20 is a similar view to Figure 7 and illustrates the end flap at the notched portion being folded outwardly upon itself.

Figure 21 is a plan view of a completed interleaved blockbottom closure according to the invention.

In carrying the invention into effect according to one convenient mode for the production of a valved bag comprising a nested series of tubes, a

series of webs of appropriate width are used to enables the longitudinal folding lines (shown in dotted lines I--I in the figure) of the tube to be formed, to lie in the same relative position with respect to the diagonal edge and notch angle at the heads and tails of the sheets and in succeeding sheets. y

When making a single-ply bag tube, sheets or blanks from webs 2 or 3 are taken. For a twoply bag sheets from webs 2 and 3 are used while for a three-ply bag, sheets from webs 2 and 3 with one from webs I or 4 are taken. When making a four-ply bag webs I to 4 are employed while for a ve-ply bag all the web sheets are utilized.

In making blockbottom open mouthed multiply bags notched and shouldered cuts are made at double bag length intervals and the double blanks are then severed midway between the notched formation by plain straight cuts so that the straight cut end may form the open mouths of the bags while the notched ends are formed into the improved blockbottoms. In continuously severing from a web the notched cuts alternate at bag length intervals, it will be understood, with plain transverse cuts.

i Where blockbottom formations are to be made at both ends of the bag tubes, as when valved bags are to be formed, arrangements are made to make the notches and shoulders at bag length intervals so that the tube ends correspond.

For present purposes it will be sufficient to describe the production of a four-ply bag.

Sheets I, 2, 3, 4 severed from the respective webs I, 2, 3, and 4 with their graduated notches and shoulders, are assembled together as shown in Figure 2, sheet I being the uppermost and intended to be the inner ply of the composite tube when formed. The sheets or blanks are arranged as to their side margins so that when the two sides of the blanks are folded over inwardly on the longitudinal dotted lines, the side marginal portions register with and overlap one another to form the tube by the application of adhesive to these margins and by pressing them into contact one with another. A tube so formed 5 is seen in Figure 3, the longitudinal seams being illustrated by the shaded longitudinal portions. It will be seen that the diagonal or oblique lines intersect one another at 6 on the folding lines at both ends of the tube so that the subsequent 3 folding of the blockbottom formations is uniform and the folding of extra thicknesses is avoided.

The notching of the blanks produces the headings or margins a, b, c, and d, on the face of the tube (see Figures 2, 3, and 4) and headings or 3 margins a', b', c', and d' on the back of the tube facing inwards. The headings a, b, c, and d are subsequently to be united to the corresponding margins a', b', c', and d' respectively.

The tube seen in Figure 3 is next given the 3 form shown in Figure 5 by folding or bending the outer end or mouth of the tube downwardly upon the face of the tube to form what may be called a side flap as at l, leaving the corresponding back portion of the tube standing as a side ap 8. In

effecting the folding of the side flap the notch corners 6 of the tube rise to form end flaps 9 and I0 which are folded inwardly flat into the position shown. At this stage adhesive may be applied to the margins a', b', c', d' for subsequently securing them to the opposite headings or margins but the adhesive may be applied at a later stage.

In the next operation the notch point B is raised and triangular parts 6a of the end fiaps 9 and Iii (shown shaded in Figure 5) are folded outwardly upon themselves by bringing the points 6 over towards the corners 6b at the edges of the tube. This operation is seen in process in regard to one corner of the bag in Figures 6 and 7. The folding outward of the end flaps simultaneously causes the side flaps 1 and 8 to be folded inwardly and in the completion of the operation the headings a, b, c, and d are folded first flat against the tube (see Figure 7 If adhesive has not already been applied the margins may now be conveniently pasted. The headings d', c', b', and a are folded over the previously folded margins a, b, c, and d so that the adhesive applied secures the heading d' upon the heading d, c upon c, b upon b, and the margin a upon the margin a, the blockbottom closure being thus secured and forming the nested tubes into a nested series of independent bags one within the other.

In the completed closure seen in Figure-8 with 5 the blockbottom flat into the plane of the tube,

only the edge of the outer sealing heading d' is observed and the point 8 coincides with the corner of the side fold of the bag tube while the triangular portion 8a overlies a similar triangular portion underneath. The outer seam formed by the heading d' extends as will be seen, practically across the width of the bag.

The nature of the extra triangular piece or pocket 6a with its point 6 will be appreciated from the perspective view shown in Figure 9, while in Figure 10 it will be seen that when the bottom is flattened about the centre line II-II (Figure 8) the rectangular form. of the corner will be seen and it will be appreciated that the triangular pocket slightly extends or increases the capacity of the bag for the given length of the tube.

Bag tubes may be closed at both ends by the improved blockbottom formation, three of the corners being formed as described above while the fourth is provided with a filling valve. Alternatively, two corners at one end of the bag may be closed as described while the other two corners are closed to` provide oppositely disposed valves. For present purposes it will be suflicient to describe the formation of a valve according to the invention as applied to one corner only, as illustrated in Figures 11 to 14.

The folded composite tube (as shown in Figure 3) at the corner at which it is desired to form the valve, is slit longitudinally as illustrated by the line II (Figure 11) in order to enable the side flaps to give greater cover for the end flap when folded in to form the valve. After slitting the front of the tube it is folded over upon itself to form side aps Ia and 8a and the end flap 9a is folded inwards (see Figure 12). In this condition the headings on the ap 8a are pasted and a rectangular piece, preferably of U-shape (such as I2, Figure 13) is applied to the V notch terminating in the point 6 to cover the same on both sides. 'Ihe side flaps Ia and 8a are then folded inwards on the chain lines III- III so that the flap 8a is laid upon the flap 'Ia to unite the corresponding headings to one another as already described, the folds taking place to include the sides of the valve flap 9a and thereby avoiding a Weakness at the corner where the slit lies. It will be seen that this valve folding operation with the exception of the formation of the slit and position of the side flap folds, corresponds to the known manner of folding a valve in the ordinary blockbottom bag.

'I'he finished valve is shown in Figure 14. An additional U-shaped piece, shown in dotted lines at I3, may be applied over the edges of the united flaps la, 8a to prevent any fouling of the plies by the filling tube, or to prevent cement or other contents with which the bag is to be filled getting between the plies.

As already indicated the opposite corner of the bag may have a similar valve if desired, which may serve the purpose of permitting the escape of air during filling. In this case an extra length of tongue or tube may be embodied in the valve.

in order to prevent the cement or contents from the filling tube blowing across the bag and through the second valve.

Applying the invention to a gusseted tube (Figure 15) the bottom forming treatment 'is similar to that already described. The front of the tube is folded down to form side flaps 'Ib and 8b as shown in Figure 15 (where one corner part of a gusseted tube is shown) with the concurrent inward folding of the end flaps as at Ilia. The

fil

points Bc are bent outwardly to form triangular portions extending over the gusset folds 4a, while the headings or margins of the side flaps 1b and 8b are adheslvely secured one to the other after 5 the manner described.

The completed closure and the corner of the gussetcd bag is seen in Figure 16 with the triangular pocket 6d extending beyond the gusset.

To form a valve in the gusseted bag the tube 10 is slit longitudinally as4 described in reference to Figure 11 and the same kind of procedure is adopted.

In carrying the invention into effect according to a modification wherein the sealing closure 15 is effected by interleaving the plies instead of having projecting headings, the sheets are cut with right-angular notches I4 (with an apex at 6e) on the longitudinal folding lines of the tube to be formed. When the sheets or blanks are cut from a web, small squares are punched out of the web when the transverse cuts are made.

These sheets are assembled together so that the notches register and with the side margins of the sheets staggered. The sides of the sheets are folded in to form a tube in the usual way, producing a tube of the character illustrated in the fragment of the tube shown in Figure 18.

Alternatively to notching the tubes the tubes may be first formed and then the corners cut off at 45 as shown at I 4 in Figure 18.

In the next step, the front or face of the tube is folded down to form the side flaps 1c and 8c whilst the end flaps are folded in as at I0b. The notched portions I4 and the points Se thereof are bent outwardly so that the end flaps are bent over upon themselves forming the triangular pockets 6i coincident with the corner portion of the bag bottom. As this is being effected the side flaps (the edges of which have been previously pasted) are folded onto one another. For example, oneedge or margin of the inner tube is first folded down and the opposite margin is then folded over it whilst the margins of the other tubes are correspondingly folded and secured together so that the margins are interleaved and a block-bottom closure (as seen in plan in Figure 21) is effected with the triangular portion Gf overlying the corner at the end of the longitudinal side fold of the tube. A valve may be formed in this bag after the manner already described by slitting one corner longitudinally.

In filling a single-valved airtight bag with cement or the like diculty is sometimes experienced by the blowing back of the cement due to the entrapped air. In order to avoid this defect the flattened bag may be perforated in known manner with a series of pin prick spaced perforations which puncture the bag from side to side and afford a relief for the air pressure.

Generally speaking, the invention is more useful in its application to the production of multiply bags than to single-ply bags, but where it is desired to make a liquid-proof bag suitable for pack- 65 ing invert sugar, or pitch or other semi-liquid material, a single-ply bag made of stout proofed paper may be used, in which case the triangular pocket or flap piece, corresponding to that shown in Figure 10, for example, is turned over and se- 70 cured by adhesive either to the bottom of the bag or to the side wall, in either case a rectangular bottom being formed and the corner closure being additionally secured by the folding and sealing over of the triangular piece.

Having now described my invention, what I aovanaa clatilis as new and desire to secure by Letters Paten f 1. A method of making blockbottom bags comprising forming sheets into flat tubes by securing their 4edges together, folding end flaps at the extremity of the folds of the tubes first inwardly and then outwardly, and folding side flaps from the faces of the tube over the outwardly folded end flaps and securing them together.

2. A method of making blockbottom bags comprising folding sheets into flat tubes, forming triangular extensions at the ends of the tube folds by folding end flaps inwardly and outwardly, and folding the faces of the tube to form side flaps and then folding the side aps over the outwardly folded end flaps and securing them together.

3. A method of making blockbottom bags comprising folding sheets into fiat bag tubes, forming triangular extensions by folding end fiaps at the ends of the tube folds, inwardly and then outwardly upon themselves, and forming side flaps from the faces of the tubes and folding them inwardly and securing them together over the outwardly folded end flaps.

4. A method of making blockbottom bags com: prising severing sheets from webs of appropriate width to form notched and shouldered end por.- tions united by oblique parts, folding the sheets to form flat tubes with the folding lines of the tubes running into the oblique parts, folding end flaps at the ends of the tube folds inwardly and then outwardly to form triangular extensions, folding the ends of the faces of the tubes over to form side flaps, and folding the side flaps over the triangular extensions and securing the side flaps together. I

5. A method of making multiply blockbottom bags comprising severing sheets with notches and shouldered portions on each sheet, assembling the sheets and forming flat tubes therefrom by securing their edges together, folding the ends of the faces of the tubes to form side flaps, folding inwards end flaps at the ends of the tube folds and then folding them outwardly to form triangular extensions, then folding the side flaps inwardly and securing them together over the outwardly folded triangular extensions.

6. A method of forming multiply blockbottom bags comprising severing sheets with notched and shouldered portions united by oblique parts, assembling the sheets together so that the oblique parts register, folding end flaps at the ends of the tube fold inwardly and then folding them outwardly to form triangular extensions, folding the ends of the faces of the tubes outwardly to form side flaps and then folding them inwardly and securing them together over the outwardly folded end flaps.

7. A method of making blockbottom bags comprising severing sheets from webs of appropriate width with notches and shoulders united by oblique parts, the shoulders and notches being of different depth to provide overlappable margins, folding the sheets to form at tubes, assembling the sheets with the intersections of the oblique parts in register, folding the faces of the ends of the tubes to form side flaps, folding the sheets on lines coincident with the intersections of the oblique parts to form fiat tubes, folding end flaps at the extremity of the tube folding lines inwardly and then outwardly to form triangular extensions, folding the side flaps over one another, and securing the opposite margins together in respective overlapping relation and over the outwardly folded end aps.

8. A method of forming blockbottom bags comprising severing sheets with V-shaped notches,

forming at tubes from the sheets by folding on lines running through the angle of the notches, folding end flaps at the extremities of the tube folds inwardly and then outwardly, while folding the end faces of the tube to form side flaps, folding the side flaps over one another and securing them together over the outwardly folded end flaps.

9. A method of forming a blockbottom multiply bag comprising severing sheets with V-shaped notches at the ends, assembling the sheets with the notches in register, folding the sheets on lines running through the angle of the notches to form tubes, folding end flaps at the extremities of the tube folds inwardly and then outwardly to form triangular extensions, whilst folding the end faces of the tubes to form side aps, folding the side flaps over one another and the end flaps, and securing them together in interleaved relation.

10. A 'method of forming gusseted blockbottom bags comprising severing sheets with notches and shoulders and oblique parts uniting the notches and shoulders, folding the blanks to form fiat tubes having longitudinal gusset folds, folding the extremities of the gusset folds inwardly while folding the end faces of the tube to form side flaps, then folding the end flaps outwardly whilst folding the side flaps over one another and over the outwardly folded end flaps and securing them together.

11. A method of forming a multiply gusseted bag comprising severing sheets with notches and shoulders of different depths united by oblique parts, assembling the sheets together with intersecting oblique parts in register, folding the assembled sheets into gusseted fiat tubes, folding end flaps at the extremity of the gusset folds inwardly whilst forming side flaps from the faces of the tubes, folding the end flaps outwardly whilst folding the side flaps inwardly over one another and over the end flaps, and uniting the overlapping margins of the side flaps together.

12. A method of making blockbottom gusseted bags comprising severing sheets with V-shaped notches, assembling the sheets together with the notches in register, folding the sheets to form gusseted flat tubes, folding end iiaps at the extremity of the gusset folds inwardly whilst forming side flaps, folding the end flaps outwardly whilst folding the side flaps inwardly over the outwardly folded end flaps, and securing the edges of the side flaps in interleaved relation.

13. A method of forming a blockbottom multiply valved bag comprising severing sheets with notches and shoulders, slitting one corner of the so tube longitudinally, assembling the sheets together and folding them toform fiat tubes, folding three of the corners of the tubes inwardly to form end aps, whilst forming side flaps in the end faces of the tube, folding the end iiaps outwardly to form triangular extensions, securing the side flaps in overlapping relation upon the outwardly folded portions of the end flaps at one end of the tube and at the other end of the tube infoldlng the slit corner of the tube to form a valve 7o flap folding the other corner to form inward and outwardly a lfolded end flap and folding the adjacent side flapsI and a portion of the sides of the valve flap inwardly, and securing the side aps over the valve and end ap.

75 14. A at blockbottom bag having triangular extensions formed by inwardly and outwardly folded end flaps and slit iiap forming a valve y which is partly folded inwards at its side with the folds of the side flaps.

15. A fiat blockbottom multiply bag having notched and shouldered portions forming side flaps, oblique parts joining the notched and shouldered parts located in end iiaps, overlapping margins on the side aps secured together and triangular extensions formed by inwardly and outwardly folded end flaps.

16. A flat blockbottom multiply bag having registerednotches in the ends of the plies, and triangular extensions formed by inwardly and outwardly folded end flaps over which side flaps are secured.

17. A flat blockbottom multiply bag having registered notches in the ends of the plies, triangular extensions formed by inwardly and outwardly folded end flaps over which the margins of side flaps are secured in interleaved relation.

18. A fiat blockbottom gusseted bag having triangular extensions formed by inwardly and outwardly folded end flaps, said extensions extending beyond the gusset folds.

19. A method of making blockbottom bags comprising securing the edges of sheets together to form at tubes with V-shaped notches at the extremities of the tube folds to facilitate folding, folding end flaps at the extremities of the folds of the tubes first inwardly and then outwardly, and folding side flaps from the faces of the tube over the outwardly folded end aps and securing them together.

20. A method of making blockbottom bags comprising folding sheets into flat tubes, forming V- shaped notches at the ends of the tube folds, forming triangular extensions at the ends of the tube folds by folding end flaps inwardly and then folding the extremities of the inwardly folded end flaps outwardly, and folding side ilaps formed from the faces of the tube over the outwardly folded end flaps and securing them together.

21. A flat blockbottom bag having triangular extensions comprising inwardly and outwardly folded end flaps, and side flaps secured together over the outwardly folded end aps.

22. A flat blockbottom bag having triangular corner extensions comprising inwardly folded end flaps the extremities of which are folded outwardly. and side flaps secured together over the outwardly folded portions of the end flaps.

23. A fiat blockbottom bag having triangular corner extensions formed from end flaps having a V-shaped notch at the extremities of the bag tube folds, one portion of the end flaps extending inwardly and another portion having said V- shaped notch 'extending outwardly, and side flaps secured together over the outwardly folded portions of the end flaps.

24. A fiat blockbottom multiply bag having triangular corner extensions comprising inwardly and outwardly folded end flaps, and side flaps with stepped end margins secured together over the outwardly folded end flaps in stepped overlapping relatlon.

25. A fiat blockbottom multiply bag having triangular corner extensions formed from end flaps having a V-shaped notch at the extremities of the bag tube folds, one portion of the end flaps extending inwardly and another portion extending outwardly. and stepped side aps secured together over the outwardly folded portions of the end flaps in stepped overlapping relation.

FOSTER GOTCH ROBINSON. 

